Donald Trump has warned Turkey of economic devastation if it attacks Kurdish forces in the wake of the US troop pullout from Syria.

The US President also urged the Kurds not to "provoke" Ankara.

His top diplomat, Secretary of State Mike Pompeo is on a whirlwind regional tour aimed at reassuring allies amid rising tensions between the US and Turkey over the fate of Washington's Syrian Kurdish allies in the fight against Islamic State (Isil).

Mr Pompeo also sought to reassure Washington's Kurdish allies, who fear the departure of American troops will allow Turkey to attack them.

Turkey had reacted angrily to suggestions Mr Trump's plan to withdraw troops was conditional on the safety of the US-backed Kurdish fighters, seen by the Turkish government as terrorists.

"Will devastate Turkey economically if they hit Kurds," Mr Trump tweeted, while pushing for the creation of a 20-mile (32km) "safe zone."

Mr Trump did not detail who would create, enforce or pay for the safe zone, or where it would be located.

Turkish President Recep Tayyip Erdogan's spokesman Ibrahim Kalin said on Twitter there was "no difference" between Isil and the Kurdish People's Protection Units (YPG) militia.

"We will continue to fight against them all," he tweeted.

US-led operations against Isil in Syria have been spearheaded on the ground by the Kurdish-dominated Syrian Democratic Forces.

Ankara sees the backbone of that alliance, the YPG, as a terrorist group linked to the Kurdistan Workers' Party (PKK) which has fought a decades-long insurgency against the Turkish state.

More than 600 people were evacuated from the last Isil enclave in eastern Syria it was reported as US-backed fighters prepared to launch a final assault.